21002124000 has 384 divisors, whose sum is σ = 80838051840. Its totient is φ = 4699392000.

The previous prime is 21002123971. The next prime is 21002124029. The reversal of 21002124000 is 42120012.

It is an interprime number because it is at equal distance from previous prime (21002123971) and next prime (21002124029).

It is a super-2 number, since 2×21002124000² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1709881 + ... + 1722119.

It is an arithmetic number, because the mean of its divisors is an integer number (210515760).

Almost surely, 2^21002124000 is an apocalyptic number.

21002124000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21002124000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40419025920).

21002124000 is an abundant number, since it is smaller than the sum of its proper divisors (59835927840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21002124000 is a wasteful number, since it uses less digits than its factorization.

21002124000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12291 (or 12273 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21002124000 its reverse (42120012), we get a palindrome (21044244012).

The spelling of 21002124000 in words is "twenty-one billion, two million, one hundred twenty-four thousand".